JP6690401B2 - Object detection device - Google Patents

Description

  The present invention relates to a technique of detecting an object located in the surroundings.

  Patent Document 1 below discloses a sonar mounted on a moving body such as a vehicle, which stops transmission waves when the vehicle is stopped. This contributes to power saving when the moving body is stopped.

JP, 2010-076577, A

  However, the above technique has a problem in that surrounding objects cannot be detected when the moving body is stopped. Therefore, in view of such a problem, in an object detection device that detects an object located in the surroundings, it is possible to satisfy the demand for saving power and the demand for detecting surrounding objects while the power is being saved. It is an object of the invention to be able to do so.

  The object detection device of the present invention includes a transmission unit (21), a reception unit (22), an output unit (23), a stop control unit (S130), and an operation control unit (S160). The transmitter (21) is configured to emit a transmission wave. The receiver (22) is configured to receive a received wave including a reflected wave of the transmitted wave.

  The output unit (23) is configured to output that the object is detected when receiving the reception wave. The stop control unit (S130) represents the state of the object detection device when the preset stop condition is satisfied, and the state in which the transmission unit stops the transmission of the transmission wave and the reception unit receives the reception wave. It is configured to be in a transmission stop state. When the receiving unit receives the received wave in the transmission stopped state, the operation control unit (S160) sets the state of the object detection device to the state in which the transmitting unit transmits the transmitting wave and the receiving unit receives the received wave. Is configured to be in the outgoing activation state that it represents.

  According to such an object detection device, since the receiving unit is operated even in the transmission stopped state in which the transmission wave is stopped, if the transmission wave transmitted from another mobile body can be received, this mobile body is received. Can be detected. Further, when the received wave is received in the transmission stopped state, the transmitter is activated, so that the surrounding objects can be detected. Therefore, it is possible to satisfy the demand for power saving and the demand for detecting surrounding objects while the power is being saved.

  Note that the reference numerals in parentheses described in this column and the claims indicate the correspondence with the specific means described in the embodiments to be described later as one aspect, and the technical scope of the present invention. It is not limited.

It is a block diagram showing a schematic structure of a driving support system. It is a flow chart which shows the object detection processing which a driving support ECU performs. It is a flow chart which shows sonar reception processing of object detection processing. It is a schematic diagram which shows the relationship with an approaching vehicle, when the own vehicle is a transmission stop state. It is a flow chart which shows a bandpass filter process of sonar reception processing. It is a schematic diagram (the 1) which shows the relationship with an approaching vehicle, when the own vehicle is a transmission operation state. It is a schematic diagram (the 2) which shows the relationship with an approaching vehicle, when the own vehicle is a transmission operation state.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings.
[1. First Embodiment]
[1-1. Constitution]
The driving support system 1 to which the present invention is applied is a system that is installed in a vehicle that is a moving body such as a passenger car and that provides driving support for the vehicle. The term “driving support” as used herein refers to performing control for assisting at least a part of the driving operation by the driver of the vehicle. The configuration of the present system may be used during automatic driving in which all driving operations by the driver of the vehicle are automated. A vehicle equipped with the driving support system 1 is also referred to as a host vehicle.

  The driving support system 1 shown in FIG. 1 includes a driving support ECU 10, a distance measuring sensor 20, a shift position sensor 25, a display unit 31, a voice output unit 32, and a pre-crash actuator 33.

The distance measuring sensor 20 includes a transmitting unit 21, a receiving unit 22, and an output unit 23. The transmitter 21 transmits a transmission wave that is a sound wave.
The receiving unit 22 receives a received wave including a reflected wave obtained by the transmitted wave being reflected by an object. That is, the transmitter 21 and the receiver 22 are configured as a sonar that transmits and receives sound waves.

  The output unit 23 is configured to output that the object is detected when receiving the received wave. The fact that an object has been detected includes position information of the object, that is, information on the distance and azimuth to the object. The azimuth information may be information indicating the sonar detection range.

  In the present embodiment, the distance measuring sensor 20 includes a plurality of transmitting units 21 and a plurality of receiving units 22 for each transmitting unit 21, and the output unit 23 identifies the position of the object using the principle of triangulation. May be.

  The shift position sensor 25 detects the position of the shift lever. The position of the shift lever is used by the driving support ECU 10 to recognize the position of the shift lever such as “P”, “R”, “N”, and “D”.

The display unit 31 is configured as a well-known display that displays an image or characters in response to an instruction from the driving support ECU 10.
The voice output unit 32 outputs a notification sound such as a buzzer sound or a voice in response to an instruction from the driving support ECU 10. The display unit 31 and the voice output unit 32 are used, for example, to notify an occupant such as a driver of an operating state of driving assistance when performing driving assistance described later.

  The pre-crash actuator 33 is an actuator for reducing damage when the host vehicle collides with an object. The pre-crash actuator 33 is configured, for example, as an actuator for increasing the brake hydraulic pressure or winding up the seat belt.

  The driving support ECU 10 is mainly composed of a well-known microcomputer having a CPU 11 and a semiconductor memory (hereinafter, memory 12) such as a RAM, a ROM, and a flash memory. Various functions of the driving support ECU 10 are realized by the CPU 11 executing a program stored in the non-transitional physical recording medium. In this example, the memory 12 corresponds to a non-transitional substantive recording medium storing a program. The non-transitional substantive recording medium means excluding electromagnetic waves from the recording medium. Further, by executing this program, the method corresponding to the program is executed. It should be noted that the number of microcomputers forming the driving support ECU 10 may be one or more.

  The driving support ECU 10 has a function of performing driving support as one of the configurations of functions realized by the CPU 11 executing a program. The method for realizing the function in the driving support ECU 10 is not limited to software, and some or all of the elements may be realized by using hardware that is a combination of logic circuits, analog circuits, and the like.

[1-2. processing]
Next, the driving support process executed by the driving support ECU 10 will be described with reference to the flowchart shown in FIG. The driving support process is a process of performing driving support in preparation for a collision with another object while suppressing the power consumption of the distance measuring sensor 20. The driving support process is started, for example, when the power of the driving support system 1 is turned on, and then repeatedly executed.

  In the driving support process, first, it is determined whether or not a stop condition that is a condition for stopping the transmission of the transmission wave in the transmission unit 21 is satisfied. Here, the shift position is detected based on the signal from the shift position sensor 25 in S110, and the shift position is determined in S120. If the shift position is the parking "P", in S130, the state of the driving support system 1, that is, the state of the distance measuring sensor 20 is transited to the transmission stop state.

  Here, the transmission stopped state means a state in which the transmission unit 21 stops transmission of transmission waves and the reception unit 22 receives reception waves. When the distance measuring sensor 20 is set in the transmission stop state in this way, the occupant of the vehicle is notified via the display unit 31 and the voice output unit 32 that the state of the driving support system 1 is in the transmission stop state. Specifically, the display unit 31 displays an image indicating that the call is in a stopped state, and the voice output unit 32 outputs a buzzer sound or a voice indicating that the call is in a stopped state.

  Then, in S140, sonar reception processing is implemented. In the sonar receiving process, as shown in FIG. 3, first, in S310, the receiving unit 22 receives a sound wave. For example, when transmission of the transmission wave is stopped by the transmission unit 21, as shown in FIG. 4, the reception unit 22 transmits the transmission wave transmitted from the distance measuring unit such as a sonar provided in another vehicle. You will receive it.

Then, in S320, the received sound pressure is amplified. In this process, for example, an amplifier such as a well-known buffer can be used.
Then, in S340, a bandpass filter process is performed. This process is a process of changing the reception sensitivity indicating the sensitivity when the reception unit 22 receives the reception wave, depending on whether the state of the distance measuring unit 20 is the transmission stop state or the transmission operation state. Specifically, the reception sensitivity in the transmission stop state is improved as compared with the reception sensitivity in the transmission operation state.

  In the band pass filter process, as shown in FIG. 5, first, in S410, it is determined whether the state of the distance measuring unit 20 is the transmission stop state or the transmission operation state. If the state of the distance measuring unit 20 is the transmission stopped state, the first band pass filter is selected in S420. Here, the first band pass filter has a wide frequency band set so that the transmission wave transmitted from another vehicle can be received. This is to enable good reception even when a sound wave of a frequency different from the sound wave transmitted by the transmitter 21 of the own vehicle is transmitted from another vehicle.

  If the state of the distance measuring unit 20 is the transmission operation state, the second band pass filter is selected in S430. The frequency band of the second bandpass filter is set narrower than that of the first bandpass filter. This is because if the transmission waves from other vehicles are widely received, the possibility of interference increases.

Subsequently, in S440, the selected bandpass filter is set, and the bandpass filter process is ended.
Upon completion of such processing, the process returns to FIG. Subsequently, in step S340, the amplified received sound wave that is an analog value is converted into a digital value. In this process, the amplified received sound wave is passed through the filter selected in the band-pass filter process described above, and a process of outputting a digital value corresponding to the voltage value of the received sound wave passing through this filter is performed. Note that well-known hardware such as an AD conversion circuit can also be used in this processing. The analog / digital conversion in S340 may be performed before the bandpass filter processing in S330. That is, the processing may be performed in the order of S340 and S330.

  Then, in S350, a process for the received sound wave is performed. When the transmitting unit 21 is transmitting the transmitted wave, the position of the object is detected as if the received sound wave is a reflected wave. When the transmitter 21 is not transmitting the transmitted wave, the receiver 22 outputs that the received wave is received. When such processing is completed, the process returns to FIG.

  Subsequently, in S150, it is determined whether or not there is a sonar wave reception indicating that the reception unit 22 has received the reception wave. If there is no sonar wave reception, the process returns to S110. If the sonar wave is received, the distance measuring unit 20 is activated in S160. The transmission operation state means a state in which the transmission section 21 transmits the transmission wave and the reception section 22 receives the reception wave.

  When the distance measuring sensor 20 is activated in this way, the occupant of the host vehicle is informed via the display unit 31 and the voice output unit 32 that the state of the driving support system 1 has been activated. Specifically, the display unit 31 displays an image indicating that it is in a call-out operation state, and the voice output unit 32 outputs a buzzer sound or a voice indicating that it is in a call-out operation state. When such processing is completed, the processing moves to S240 described later.

  If the shift position is the parking "P" in the process of S120, sonar transmission for causing the transmitting unit 21 to transmit a sound wave is performed in S210. Subsequently, in S220, sonar reception processing similar to that described above is performed. When this sonar reception process is completed, obstacle control is performed in S230.

  Here, the anti-obstacle control prepares for the collision of the other vehicle with the own vehicle when the other object approaching the own vehicle is highly likely to collide with the own vehicle. Specifically, the position of another object approaching the own vehicle and the moving direction of the object are recognized by a known process, and a collision is determined.

  For example, as shown in FIG. 6, in the case of an approaching vehicle 52 that is a vehicle approaching another object, if the approaching vehicle 52 is moving in the direction of collision with the host vehicle 51, there is a high possibility of collision. As a result, the pre-crash actuator 33 is operated. In other words, prepare for a collision.

  Further, as shown in FIG. 7, when the approaching vehicle 52 is approaching the host vehicle 51 but is likely to pass by the host vehicle 51 without colliding with the host vehicle 51, the possibility of collision is low. As a matter of fact, the pre-crash actuator 33 is not operated.

  Succeedingly, in S240, it is determined whether or not an object (obstacle) such as the approaching vehicle 52 is detected. If an object is detected, the process returns to S210. If no object is detected, the object detection process ends. When the process shifts to S240 immediately after the wakeup which is the process of S160, the process is performed assuming that there is an obstacle in S240.

[1-3. effect]
According to the first embodiment described in detail above, the following effects can be obtained.
(1a) The driving support system 1 described above includes a transmission unit 21, a reception unit 22, an output unit 23, and the driving support ECU 10. The transmitter 21 is configured to emit a transmission wave. The receiver 22 is configured to receive a received wave including a reflected wave of the transmitted wave.

  The output unit 23 is configured to output that the object is detected when receiving the received wave. The driving assistance ECU 10 indicates the state of the driving assistance system 1 when the preset stop condition is satisfied, that is, the state in which the transmission unit 21 stops transmitting the transmission wave and the reception unit 22 receives the reception wave. It is configured to be in a transmission stop state. Further, when the reception unit 22 receives the reception wave in the transmission stop state, the transmission of the state of the driving support system 1 indicating the state in which the transmission unit 21 transmits the transmission wave and the reception unit 22 receives the reception wave. It is configured to be activated.

  According to the driving support system 1 as described above, the reception unit 22 is operated even in the transmission stopped state in which the transmission wave is stopped. Therefore, if the transmission wave transmitted from another mobile body can be received, It can detect moving objects. Further, when the reception wave is received in the transmission stopped state, the transmitter 21 is activated, so that the surrounding objects can be detected. Therefore, it is possible to satisfy the demand for power saving and the demand for detecting surrounding objects while the power is being saved.

(1b) In the driving support system 1 described above, the transmission unit 21 and the reception unit 22 are configured as a sonar that transmits and receives sound waves.
According to such a driving support system 1, in the configuration of transmitting and receiving sound waves, it is possible to meet the demand for power saving and the demand for detecting surrounding objects while power saving is being performed.

  (1c) In the driving support system 1 described above, the driving support ECU 10 sets the reception sensitivity that represents the sensitivity when the reception unit 22 receives the reception wave when the driving support system 1 is in the transmission stopped state, to the driving support system. 1 is configured to improve the reception sensitivity when the transmitter 1 is in the transmission operation state.

  According to such a driving support system 1, the sensitivity can be improved so that the transmission wave emitted by another moving body can be easily received when the transmission is stopped. Further, since the sensitivity is lower in the transmission operation state than in the transmission stop state, the reflected wave of the transmission wave transmitted by the transmission unit 21 is less likely to interfere with the transmission wave emitted by another moving body. be able to.

  (1d) In the driving support system 1 described above, the driving support ECU 10 prepares for a collision of a moving body with another object when the state of the driving support system 1 is set to the transmission operation state.

According to such a driving support system 1, when a transmission wave from another moving body is detected, it is possible to prepare for a collision with another moving body.
(1e) In the driving support system 1 described above, the driving support ECU 10 notifies the occupant of the moving body whether the state of the driving support system 1 is the transmission stop state or the transmission operation state.

According to such a driving support system 1, it is possible to notify the occupant of the state of the driving support system 1.
[2. Other Embodiments]
Although the embodiments for implementing the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and various modifications can be implemented.

  (2a) In the above embodiment, the transmission unit 21 is configured to emit a sound wave, but the configuration is not limited to this. For example, electromagnetic waves such as radio waves and light waves may be transmitted as transmission waves. In this case, the receiving unit 22 may be configured to be able to receive the reflected wave of the electromagnetic wave.

  (2b) In the above-described embodiment, the receivable frequency band is set wide as a configuration for improving the sensitivity of the reception unit 22 when the driving support system 1 is in the transmission stopped state. A method such as changing the dynamic range to be wider may be adopted.

  (2c) In the above embodiment, the signal from the shift position sensor 25 is used as the stop condition that is a condition for stopping the transmission of the transmission wave in the transmission unit 21, but, for example, the speed sensor indicates a speed equal to or lower than a certain speed. In some cases, any condition can be used as the stop condition.

  (2d) The functions of one constituent element in the above-described embodiment may be distributed as a plurality of constituent elements, or the functions of a plurality of constituent elements may be integrated into one constituent element. Moreover, you may omit a part of structure of the said embodiment. Further, at least a part of the configuration of the above-described embodiment may be added or replaced with respect to the configuration of the other above-described embodiment. Note that all aspects included in the technical idea specified only by the wording recited in the claims are embodiments of the present disclosure.

  (2e) In addition to the driving support system 1 described above, a device that is a component of the driving support system 1, a program for causing a computer to function as the driving support system 1, and a non-transitional type such as a semiconductor memory in which the program is recorded. The present disclosure can also be realized in various forms such as an actual recording medium and a driving support method.

[3. Correspondence between Configuration of Embodiment and Configuration of Present Invention]
The driving support system 1 in the above embodiment corresponds to an example of the object detection device according to the present invention. Further, of the processes executed by the driving support ECU 10 in the above-described embodiment, the process of S130 corresponds to an example of the stop control unit and the notification unit in the present invention, and the process of S160 in the above-described embodiment is the operation control in the present invention. It corresponds to an example of the section and the notification section. Further, in the above embodiment, the process of S230 corresponds to an example of the collision preparation unit in the present invention, and in the above embodiment, the processes of S410, S420, S430, and S440 correspond to an example of the sensitivity control unit in the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Driving support system, 10 ... Driving support ECU, 11 ... CPU, 12 ... Memory, 20 ... Distance measurement sensor, 20 ... Distance measurement part, 21 ... Transmission part, 22 ... Reception part, 23 ... Output part, 25 ... Shift Position sensor, 31 ... Display unit, 32 ... Voice output unit, 33 ... Pre-crash actuator, 51 ... Own vehicle, 52 ... Approaching vehicle.

Claims (5)

An object detection device (1) mounted on a moving body and configured to detect an object located around the moving body, comprising:
A transmitter (21) configured to emit a transmitted wave;
A receiver (22) configured to receive a received wave including a reflected wave of the transmitted wave ;
When stop condition is satisfied, which is pre-Me set, the state of the object detecting device, it stops the transmission of the transmission wave to the transmitting unit, and a transmitting stop state indicating a state to receive the received wave to the receiving unit A stop control unit (S130) configured as described above,
In the transmission stopped state, when the receiving unit receives the received wave, the transmission operation indicating the state of the object detection device is a state in which the transmitting unit transmits the transmitting wave and the receiving unit receives the receiving wave. An operation control unit (S160) configured to set the state,
An output unit (23) configured to output that the object is detected when the receiving unit receives the received wave in the transmitting operation state;
An object detection device equipped with. The object detection device according to claim 1, wherein
The object detection device, wherein the transmitter and the receiver are configured as a sonar that transmits and receives sound waves. The object detection device according to claim 1 or 2, wherein
When the object detection apparatus of the calling stopped, the reception sensitivity representing the sensitivity in the receiving unit receives the reception wave, so that the object detection apparatus is improved than the reception sensitivity when the calling operation state Sensitivity control unit (S410, S420, S430, S440)
An object detection device further provided with. The object detection device according to any one of claims 1 to 3,
A collision preparation unit (S230) that prepares for collision with the moving body by another object when the operation control unit is in the transmission operation state.
An object detection device further provided with. The object detection device according to claim 1, wherein
Notification unit (S130, S160) for informing the occupant of the moving body whether the state of the object detection device is the transmission stop state or the transmission operation state.
An object detection device further provided with.

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